Smoking articles and method for incorporating salts of lanthanide metals for reducing TPM cytotoxicity and targeted constituents in tobacco smoke

ABSTRACT

Provided is a smoking article and method for reducing TPM cytotoxicity and targeted constituents in mainstream smoke. The smoking article includes tobacco material including a salt of a lanthanide metal. The method includes combining a salt of a lanthanide metal, water, and optionally glycerin to produce a solution that is applied to tobacco material. Preferably, the salt is an acetate, a sulfate, or a gluconate.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119(e) to U.S.provisional Application No. 60/924,796, filed May 31, 2007, the entirecontent of which is incorporated herein by reference.

BACKGROUND

Smoking articles, such as cigarettes, produce both mainstream smokeduring a puff and side stream smoke during static burning. Compounds,such as hydroquinone, resorcinol, naphthalene, and catechol are found inthe particulate phase of mainstream smoke. Such tobacco smokeconstituents have been targeted for reduction.

SUMMARY

Provided is a smoking article including tobacco material that is treatedwith a salt of lanthanide metal and optionally glycerin and a method forreducing TPM cytotoxicity and targeted constituents in tobacco smoke bytreating tobacco material with the salts of a lanthanide metal.Preferably, the salts are acetates, sulfates, or gluconates.

Preferably, the method includes selecting a salt of a lanthanide metaland dissolving the salt in water to form a solution. In an embodiment,the tobacco material is weighed and placed in a tumbling device.Preferably, the solution is added drop wise to or sprayed onto thetobacco material, while the tobacco material is tumbled so that thesolution is applied throughout the tobacco material.

In an embodiment, the solution is sprayed onto the tobacco materialwhile in the tumbling device.

In a preferred embodiment, the tobacco material is dried to evaporatethe water, and then incorporated into a smoking article.

In a preferred embodiment, the solution also includes glycerin.Preferably, the glycerin enhances the reductions in cytotoxicity,mutagenicity and reduces the relative amount of targeted constituents ofmainstream smoke when compared to the use of the salt of a lanthanidemetal alone. While glycerin alone can also reduce cytotoxicity andmutagenicity, the combination of glycerin and the salt of the lanthanidemetal is also enhanced when compared to use of glycerin alone.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of an embodiment of a smoking article withreduced cytotoxicity and mutagenicity.

DETAILED DESCRIPTION

As described herein and shown in FIG. 1, a smoking article 10 withreduced TPM toxicity and targeted constituents is provided.

Preferably, the smoking article 10 contains tobacco material 12contacted with a salt of a lanthanide metal 14 that aids in reducing thecontent of compounds, such as hydroquinone, resorcinol, naphthalene, andcatechol, in the particulate phase of mainstream smoke. Preferably, thecytotoxicity and mutagenicity is also reduced by the inclusion of thesalt of a lanthanide metal 14.

In a preferred embodiment, the salt 14 is an acetate, a sulfate, or agluconate. Most preferably, the salt 14 is an acetate salt of alanthanide metal.

The term “smoking article” includes cigarettes, pipes, cigars, andcigarillos. Non-traditional cigarettes such as cigarettes for electricalsmoking systems are also included in the definition of smoking articlesor cigarettes generally.

Preferably, the smoking article 10 is a cigarette, which containstobacco material 12. In a preferred embodiment, the cigarette includes afilter. In an embodiment, the cigarette may also contain at least onesorbent.

A traditional cigarette typically contains two sections, atobacco-containing portion sometimes referred to as the tobacco orcigarette rod, and a filter portion which may be referred to as afiltration zone. Tipping paper typically surrounds the filter, whichforms the buccal end of the cigarette. The tipping paper overlaps withthe tobacco rod in order to hold the filter and tobacco rod together.The tobacco rod, or tobacco containing element of the cigarette includesthe paper wrapper in which the tobacco is wrapped and the adhesiveholding the seams of the paper wrapper together. The tobacco rod has afirst end which is integrally attached to the filter and a second endwhich is lit or heated for smoking the tobacco. When the tobacco rod islit or heated for smoking, the smoke travels from the lit end downstreamto the filter end of the tobacco rod and further downstream through thefilter.

The “upstream” and “downstream” relative positions between filtersegments and other features are described in relation to the directionof mainstream smoke as it is drawn from a tobacco rod and though amulti-component filter during a puff.

In a preferred embodiment, the filter of the smoking article includes asorbent. A “sorbent” is a substance that can condense or hold moleculesof other substances on its surface, and/or can take up other substances,i.e., through penetration of the other substances into its innerstructure, or into its pores. Accordingly, the term “sorbent” as usedherein refers to either an adsorbent, an absorbent, or a substance thatcan function as both an adsorbent and an absorbent. Preferred sorbentsinclude various forms of activated carbon, molecular sieves, such aszeolites, and mixtures thereof.

Examples of suitable types of tobacco materials that may be usedinclude, but are not limited to, flue-cured tobacco, Burley tobacco,Maryland tobacco, Oriental tobacco, rare tobacco, specialty tobacco,blends thereof and the like. The tobacco material may be provided in anysuitable form, including, but not limited to, tobacco lamina, processedtobacco materials, such as volume expanded or puffed tobacco, processedtobacco stems, such as cut-rolled or cut-puffed stems, reconstitutedtobacco materials, blends thereof, and the like. Tobacco substitutes mayalso be used.

Humectants, flavorants, and sweeteners may also be blended with thetobacco material.

Suitable humectants that can be used with the tobacco material include,without limitation, glycerol, glycerin, triethylene glycol and propyleneglycol.

In a preferred embodiment, the tobacco material 12 is treated with asolution including a salt of a lanthanide metal 14. Preferably, thelanthanide metal is lanthanum, cerium, praseodymium, neodymium,promethium, samarium, europium, gadolinium, terbium, dysprosium,holmium, erbium, thulium, ytterbium, or lutetium.

Also provided is a method for treating tobacco materials with a solutionincluding a salt of a lanthanide metal. The method includes forming asolution of water and the salt of a lanthanide metal. Water is used todissolve the salt of a lanthanide metal, and is therefore only needed inan amount suitable to dissolve the salt.

The salt of the lanthanide metal is added to the tobacco material in anamount of about from 0.25% to about 25% by weight of the salt of alanthanide metal. More preferably, the salt of a lanthanide metal isadded to the tobacco material in an amount of about 0.1% to about 10% byweight of the lanthanide metal.

In an embodiment, glycerin 16 is added to the tobacco material 12 in anamount of about 2% to about 25% by weight of the tobacco. Morepreferably, glycerin 16 is added to the tobacco material 12 in an amountof about 5% to about 15% by weight of the tobacco material 12. Thisportion of glycerin 16 is in addition to the use, if any, of glycerin 16as a humectant.

If too much glycerin 16 is added, the wrapping paper 20 of the smokingarticle 10 may become too moist.

Preferably, the glycerin 16 enhances the reduction of cytotoxicity andmutagenicity when used in conjunction with the salt of a lanthanidemetal 14. As shown in Tables 1 and 2 below, neither glycerin 16 nor thesalt of the lanthanide metal 14 reduces the cytotoxicity or mutagenicityas much as the combination of glycerin 16 and the salt 14, though bothglycerin 16 and the salt 14 can be independently effective in reducingcytotoxicity and mutagenicity.

In an embodiment, after the solution is formed, the tobacco material 12is placed in a tumbling device and drops of the solution are addedthrough a nozzle as the tobacco tumbles so that the solution is spreadthroughout the tobacco material. In another embodiment, the solution issprayed onto the tobacco material while in the tumbling device.

The tobacco material is then dried to evaporate the water, and processedfor inclusion in a smoking article.

EXAMPLE 1

About 3.2 g of solid La(OAc)₃.xH₂O is dissolved in about 20 g ofdeionized water in a vial. About 40 g of tobacco material is placed in atumbling device. The solution is sprayed through a nozzle onto thetobacco material as the tobacco material is tumbled. The treated tobaccois dried to evaporate the water and equilibrated in a conditioned room.

Table 1, below, shows the results of FTC tests of the tobacco treatedwith acetate salts of a lanthanide metal incorporated into a smokingarticle and smoked. Under FTC conditions, the 3rd and 4th puffs of themainstream TPM are collected. The relative phenolic and PAH contents areobtained by GC/MS methods. The TPM cytotoxicity data is obtained usingthe Neutral Red Uptake, while mutagenicity data is obtained using Amesassays.

TABLE 1 8% La(OAc)₃•xH₂O 7.4% 8% 8.2% Compounds (x ≦ 2) Ce(OAc)₃•H₂OEu(OAc)₃•H₂O Lu(OAc)₃•H₂O catechol −41% −54% −48% −33% HQ −60% −23% −39%−49% resorcinol −56% — −33% −39% Naphthalene −51% −47% −54% −33%Cytotoxicity −25% — — — Mutagenicity −46% — −21% — *— No significantchange (absolute change <20%)

In all cases, the cytotoxicity is reduced. The mutagenicity of themainstream smoke is only reduced when the tobacco was treated with 8%La(OAc)₃.xH₂O, 8% Eu(OAc)₃.H₂O, or 8.2% Lu(OAc)₃.H₂O.

EXAMPLE 2

About 4.0 g of glycerin is dissolved in about 20 g of deionized water.About 3.2 g of solid La(OAc)₃.xH₂O is added to form a solution. About 40g of tobacco material is placed in a tumbling device. The solution issprayed into the tumbling device through a spraying nozzle as thetobacco material is tumbled. The treated tobacco is dried andequilibrated in a conditioned room.

Table 2 shows the results of an FTC test of the tobacco material treatedwith glycerin and the salt of a lanthanide metal is incorporated into asmoking article and smoked. Under FTC conditions, the 3rd and 4th puffsof the mainstream TPM are collected. The relative phenolic and PAHcontents are obtained by GC/MS methods. The TPM cytotoxicity andmutagenicity data are obtained using Neutral Red Uptake and Ames assays,respectively.

TABLE 2 8% 7.4% 7.7% 8.2% La(OAc)₃•xH₂O Ce(OAc)₃•H₂O Eu(OAc)₃•H₂OLu(OAc)₃•H₂O 10% Compounds 10% glycerin 10% glycerin 10% glycerin 10%glycerin glycerin phenol −74% −65% −73% −74% −69% o−cresol −58% −53%−62% −63% −66% m/p−cresol −66% −52% −61% −62% −63% catechol −45% −39%−40% −37% −41% HQ −56% −48% −50% −62% −27% resorcinol −53% −80% −71%−65% — Naphthalene −61% — −29% −51% −63% Fluorene −31% — −21% −21% −41%Phenantrene −37% — — — −26% Cytotoxicity −40% −36% −47% −44% −22%Mutagenicity −40% −41% −56% −45% — *—: No significant change (absolutechange <20%)

As seen in Table 2, the cytotoxicity and mutagenicity for all samplestreated with glycerin and a salt of a lanthanide metal is greatlyreduced compared to tobacco treated with glycerin alone.

As compared to Table 1, the addition of glycerin to the solutionimproves the smoke chemistry of the cigarettes, resulting in enhancedreduction in TPM cytotoxicity and mutagenicity, as compared to thecigarettes containing tobacco treated with only an acetate salt of alanthanide metal.

Test results indicate that the combination of glycerin and a salt of alanthanide metal is most effective for reducing cytotoxicity andmutagenicity, whereas the salt or glycerin alone shows only minorreductions.

While the foregoing has been described in detail with reference tospecific embodiments thereof, it will be apparent to one skilled in theart that various changes and modifications may be made, and equivalentsthereof employed, without departing from the scope of the claims.

1. A smoking article comprising: a portion of tobacco material includinga salt of a lanthanide metal wherein said salt is an acetate, a sulfate,or a gluconate.
 2. The smoking article of claim 1, wherein said portionof tobacco material further includes glycerin.
 3. The smoking article ofclaim 2, wherein glycerin is included in said smoking article in anamount of about 2% to about 25%.
 4. The smoking article of claim 2,wherein glycerin is included in said smoking article in an amount ofabout 5% to about 15%.
 5. The smoking article of claim 1, wherein saidacetate salt of a lanthanide is selected from the group consisting ofLa(OAc)₃.xH₂O, Ce(OAc)₃.H₂O, Eu(OAc)₃.H₂O, Lu(OAc)₃.H₂O, andcombinations thereof.
 6. The smoking article of claim 1, wherein saidsmoking article includes said salt of a lanthanide metal in an amount ofabout 0.25% to about 25% by weight of the salt of a lanthanide metal. 7.The smoking article of claim 1, further including (a) humectants; (b)sweeteners; and/or (c) flavorants.
 8. A method of treating tobacco smokeproduced by the smoking article of claim 1, wherein the salt of thelanthanide reduces cytotoxicity of the tobacco smoke by about 1% toabout 60%.
 9. A method of treating tobacco smoke produced by the smokingarticle of claim 2, wherein salt of the lanthanide and glycerin reducesthe cytotoxicity and mutagenicity of tobacco smoke produced by saidsmoking article by about 20% to about 70%.
 10. A method of treatingtobacco smoke produced by the smoking article of claim 1, wherein thesalt of the lanthanide reduces the mutagenicity of said mainstream smokeby about 1% to about 50%.
 11. A method of treating tobacco smokeproduced by the smoking article of claim 1, wherein the salt of thelanthanide metal reduces the presence of catechol, hydroquinone,resorcinol, and naphthalene by about 1% to about 80%.
 12. A method ofmaking a smoking article for reducing TPM cytotoxicity and mutagenicityin smoke comprising: contacting a portion of tobacco material with asolution containing a salt of a lanthanide metal to form a treatedportion of tobacco material; and incorporating said treated portion oftobacco material into a smoking article, wherein said salt of alanthanide metal is an acetate, a sulfate, or a gluconate.
 13. Themethod of claim 12, wherein said solution further includes glycerin. 14.The method of claim 13, wherein said glycerin is included in saidsolution in an amount of about 2% to about 25%.
 15. The method of claim13, wherein said glycerin is included in said solution in an amount ofabout 5% to about 15%.
 16. The method of claim 12, further includingdrying said treated portion of tobacco material.
 17. The method of claim12, wherein said salt of a lanthanide metal is sprayed onto said portionof tobacco material, added drop wise to said portion of tobaccomaterial, and/or said portion of tobacco material is placed in atumbling device prior to contacting said portion of tobacco materialwith said solution.
 18. The method of claim 12, wherein said treatedportion of tobacco material includes said salt of a lanthanide metal inan amount of about 0.25% to about 25% by weight of said salt of alanthanide metal.
 19. The method claim 13, wherein (i) when said portionof tobacco material is treated with said solution containing glycerinand a salt of a lanthanide metal, the cytotoxicity and mutagenicity isreduced by about 20% to about 70%, (ii) said smoking article produces amainstream smoke having a cytotoxicity that is reduced by about 1% toabout 60% when said tobacco material is treated with said solutionincluding a salt of a lanthanide metal, (iii) the mutagenicity of saidmainstream smoke is reduced by about 1% to about 50% when said tobaccomaterial is treated with a salt of a lanthanide metal, and/or (iv) saidmainstream smoke has a reduced presence of catechol, hydroquinone,resorcinol, and naphthalene by about 1% to about 80%.
 20. The method ofclaim 12, wherein said lanthanide metal is selected from the groupconsisting of lanthanum, cerium, praseodymium, neodymium, promethium,samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium,thulium, ytterbium, lutetium, and combinations thereof.